Tuesday, March 2, 2010

Widely Used Agricultural Pesticide Causes Sex Change

There is something strange in the water indeed!!

In my previous life as a scientific researcher, I spent hours and hours conducting studies on atrazine and it's effects on the endocrine system. Last year the EPA approved of its continued use despite results from various laboratories throughout the country arguing that more stringent regulation may be necessary. This past Monday, the prestigious journal Proceedings of the National Academy of Sciences of the United States of America published an article from my former laboratory called: "Atrazine induces complete feminization and chemical castration in male African clawed frogs (Xenopus laevis)"

From the title of the paper you can probably guess what they were able to find.

Male frogs not only showed signs of demasculinization, but actually became fully female and had the ability to lay viable eggs. Essentially, they had a chemical sex change through environmental exposure! If that isn't crazy enough, the levels at which these frogs were exposed to atrazine are thousands of times below the level currently allowable in drinking water.

Read the abstract from PNAS.

Here are some quotable quotes from around the news world:

About 75% of stream water samples and 40% of groundwater samples contain atrazine, according to the U.S. Geological Survey. The Natural Resources Defense Council, an environmental advocacy group, detected atrazine in 90% of tap water samples from 139 water systems. Inexpensive faucet-top water filters can remove the chemical" - USA Today, March 1, 2010

Atrazine can be transported more than 1,000 kilometers (620 miles) from the point of application via rainfall and, as a result, contaminates otherwise pristine habitats - AFP, March 1, 2010

Approximately 80 million pounds (36,287 tonnes) are applied annually in the United States alone, and atrazine is the most common pesticide contaminant of ground and surface water.

The negative impacts on wild amphibians is especially concerning given that the dose examined here (2.5 ppb) is in the range that animals experience year-round in areas where atrazine is used as well within levels found in rainfall, in which levels can exceed 100 ppb in the Midwestern United States - Reuters, March 2, 2010

Atrazine was banned in the European Union (EU) in 2004 because of its persistent groundwater contamination. In the United States, however, atrazine is one of the most widely used herbicides, with 76 million pounds of it applied each year, in spite of the restriction that used to be imposed. It is probably the most commonly used herbicide in the world, and is used in about 80 countries worldwide. Its endocrine disruptor effects, possible carcinogenic effect, and epidemiological connection to low sperm levels in men has led several researchers to call for banning it in the US. - Wikipedia

Men with higher levels of three commonly used farming pesticides—alachlor, atrazine, and diazinon—in their bodies were much more likely to have a low sperm count than men who showed low levels of the pesticides. - National Geographic, April 2005